PPDL Picture of the Week for
January 23, 2012

Mild Weather Brings Up The Bulbs

B. Rosie Lerner, Extension Consumer Horticulturist, Purdue University

Mild winter weather can often cause spring flowering bulbs to break out of dormancy, showing foliage above the ground in January or February, and sometimes even blooming. The most dramatic response is with early flowering bulbs, such as snowdrops, early tulips, daffodils and crocus.

So what will happen to them now that winter has returned? Leaves will likely be nipped back as temperatures drop back down below freezing, though snow is good insulation. In most cases, flower buds will remain protected inside the bulb below ground. Those flowers and flower buds that did emerge will also be nipped back by freezing temperatures. However, the bulbs themselves will survive and come back next year, even if the flowers don't make it to spring this year.

There's not much a gardener can do to prevent nature from taking its course. Mulching over emerged plants might smother them and would actually encourage growth by warming the soil further. And we still have lots more winter to get through before we know how the plants will fare.

Frequent freezing and thawing will also cause bulbs to heave out of the ground, the more shallow the bulb, the more likely to heave. Its best to replant these bulbs immediately, if the ground is not frozen.

Click image to enlarge

These snowdrops were blooming during the first couple of weeks in January, 2012 in West Lafayette, IN.  Note a few of the heaved bulbs laying on the surface of the soil.

Purdue Plant & Pest Diagnostic Lab Purdue Cooperative Extension Service